Utility meters, including mechanical, electromechanical, and solid state meters, are well known and have been used for many years to measure the consumption of resources such as water, gas and electricity. Water meters, for example, generate data indicative of the consumption of water, where such data is used for billing purposes. Initially, utility meters were mechanical devices. As electronic technology advanced, such technology became smaller and less expensive, and thus, more suitable for use in the highly competitive and cost sensitive utility meter market. As such, the use of electromechanical (hybrid meters) and electronic meters has become more common. Indeed, most modem electricity meters are electronic meters (static meters).
While there are various techniques for measuring fluid flow, most fluid meters are still electromechanical devices. Such fluid meters frequently comprise major components such as a fluid chamber and a register. The fluid chamber often has a fluid input and a fluid output which allows a fluid to flow through the fluid chamber. Typically, a rotating-device is placed within the fluid chamber in the path of fluid flow where such fluid flow causes the rotating device to rotate in proportion to the rate of fluid flowing through the meter.
Various means exists for making the rotations of such a rotating device detectable by components in the register. For example, in many prior art meters, the rotating-device and components in the register are magnetically coupled. In such meters, the rotating-device may be constructed from a magnetic material or have magnetic material associated with the rotating-device. As the rotating device rotates in response to fluid flow through the meter, a rotating magnetic field is created. Components in the register count the number of rotations and use such data to determine and display consumption data. U.S. Pat. No. 6,604,434 issued to Hamilton et al. discloses such a meter and such patent is incorporated by this reference for all purposes.
Traditionally, meter reading personnel would periodically travel to each site where a utility meter was installed, inspect a meter installation and manually record the consumption data. The customer would then receive a bill based on such collected data. Today, modern meters are increasingly equipped with Automatic Meter Reading (AMR) capabilities which provide utility meters with the capability of automatically communicating consumption data to a remote location. Such technology greatly simplifies and lowers the cost of collecting consumption data for billing purposes. However, utility companies have installed millions of utility meters that do not have AMR capabilities. For utility companies to upgrade such meters with AMR capabilities, it has been necessary to replace the entire meter or major meter components (e.g. one or both of the register and fluid chamber). Such upgrades are very expensive. Consequently, there is a need for technology that allows utility companies to upgrade non-AMR equipped utility meters with AMR technology without requiring the replacement of major components of the meter.
Additionally, as noted above, utility meters collect consumption data used by a utility company to bill a utility company's customers. Thus, accuracy in collecting consumption data is critical. Similarly, utility meters are expected to operate accurately for years without failure. Finally, utility companies expect such functionality at the lowest possible price. Consequently, there is a need for a system for adding AMR capabilities to old and new utility meters that is accurate, dependable and cost effective.
Yet another issue that designers of utility meter technology face is supplying power to the meter electronics. In many utility meter environments, easily accessible power from an electrical utility grid is not available. As a result, such meter technology is often powered by a depletable power source such as batteries. Therefore there is a need for AMR technology designed for minimal power consumption so that such technology may be powered for extended periods of time by depletable power sources. In addition, for some installations, there is a need for an apparatus and method for recharging the depletable power source.
To minimize power consumption and component stress, prior art meters employ AMR technology that places the AMR system in an off state. When data is needed from such prior art AMR equipped systems, a remote AMR reader sends a wakeup signal to the AMR equipped meter to activate the transmitter. The transmitter then transmits data to the remote AMR reader. While such a system works well, it requires the remote AMR reader to have relatively expensive transmitter capabilities and the AMR systems installed at the meter to have relatively expensive receiver capabilities. Thus, while power consumption may be minimized for such a system, the technology needed to transmit and receive a wakeup signal adds cost of the system. Consequently, there is a need for an AMR system that can place the AMR transmitter in a sleep mode without requiring a wakeup signal.
Another problem with some prior art AMR systems that transmit a signal to a remote location is that the low cost design of one component might add cost to a second component. For example, some prior art AMR transmitters may be designed for low cost by using lower quality, relatively less expensive components. For such transmitters, the carrier frequency of the transmitter signal may drift over time or the power level of the transmitted signal may weaken over time. While such systems may be designed to minimize the cost of the AMR transmitter technology located at the utility meter, such a design adds costs to the receiver electronics located at a remote location. Thus, there is a need for an AMR transmitter design that minimizes transmitter costs without adding significant costs to the receiver technology design.
Another issue the designers of AMR systems face relates to the diversity of register designs among different meter manufactures and the diverse communication protocols used by such registers. In the area of water meters, for example, while most major water meter manufacturers include a register design incorporating a three conductor interface to facilitate communication with electronic device outside the register (such as a transmitter), such registers use different communication protocols. In most prior art meters, the AMR transmitter communication hardware must be manually configured before the AMR transmitter can communicate with the meter register. Manually configuring an AMR transmitter with the proper communication protocol from a plurality of possible communication protocols is undesirable as it as cost to the AMR transmitter installation process, requires extra training for meter installation personnel, and provides an opportunity for human error. U.S. Pat. No. 5,523,751 issued to Byford et al., incorporated by this reference for all purposes, discloses a meter reading apparatus, such as a hand held probe, which has the ability to automatically communication with a plurality of data sources. While the Byford et al. invention works well for its intended purpose, such a method consumes too much power for a transmitter powered by a depletable power source installed at a customer site. Thus, there is a need for an auto communication configuration apparatus and method that minimizes power consumption and is designed for devices powered by depletable power sources and installed at remote customer locations.